Methods for producing synthesis gas are well known from practice.
An example of a method for producing synthesis gas is described in EP-A-0 400 740.
Generally, a stream containing a carbonaceous material, such as coal, brown coal, peat, wood, coke, soot, or other gaseous, liquid or solid fuel or mixture thereof, is partially combusted in a gasification reactor using an oxygen containing gas such as substantially pure oxygen or (optionally oxygen enriched) air or the like, thereby obtaining a.o. synthesis gas (CO and H2), CO2 and a slag. The slag formed during the partial combustion drops down and is drained through an outlet located at or near the reactor bottom.
The hot product gas, i.e. raw synthesis gas, usually contains sticky particles that lose their stickiness upon cooling. These sticky particles in the raw synthesis gas may cause problems downstream of the gasification reactor where the raw synthesis gas is further processed, since undesirable deposits of the sticky particles on, for example, walls, valves or outlets may adversely affect the process. Moreover such deposits are hard to remove.
Therefore, the raw synthesis gas is quenched in a quench section which is located downstream of the gasification reactor. In the quench section a suitable quench medium such as water vapour is introduced into the raw synthesis gas in order to cool it.
A problem of producing synthesis gas is that it is a highly energy consuming process. Therefore, there exists a constant need to improve the efficiency of the process, while at the same time minimizing the capital investments needed.